1. Field of the Invention
The present invention relates to a self-service checkout system, and more particularly to a method and apparatus for optimizing a security attributes database for a plurality of products in a self-service checkout apparatus.
2. The Related Prior Art
U.S. Pat. Nos. 4,676,343, 4,792,018 and 5,340,970, commonly-assigned with the present application, present systems for operator-unattended checkout with particular concern for detection of customer fraud and deterrence of the same.
In U.S. Pat. No. 4,676,343 (hereafter “the '343 patent”), an article selected for purchase has its universal product code (UPC) scanned by a code reader and the code reader output signals effect the fetching from storage of a signal indicative of a measurable characteristic of the article. A measurable characteristic of an article may include a physical characteristic such as the length, width, weight, volume and the like.
The article is placed on a conveyor and led into a security zone defined by inlet and outlet light curtains including a scale for measuring item weight. In the security zone, the measurable characteristic of the selected article is measured by a sensor and the sensor provides an output signal indicative of the measurement. A comparison is made of the sensor output signal and the fetched signal and, if the comparison is favorable, the conveyor continues to move in an article acceptance sense to deliver the article to a bagging area. Should the comparison be negative, however, the movement of the conveyor is reversed and the article placed on the conveyor is returned to the customer.
The system thus detects and rejects customer fraud in substituting a more expensive article having diverse characteristics from those of the article scanned for UPC, additionally the system protects the shopper from being over charged. Beyond the described anti-fraud facility, conveyor movement is reversed on violations of the security zone, as by efforts of a customer to reach into the security zone to substitute articles.
In U.S. Pat. No. 4,792,018, (hereafter the “'018 patent”), various security-related improvements are disclosed, one of which is the reconfiguration of the inlet light curtain to sense the size of a selected article in addition to the role of the curtain in guarding the security zone from fraudulent customer interaction. While the '343 patent contemplates article size also as a measurable article characteristic, the '018 patent discloses the capacity for providing the measured article size information store itself from the inlet light curtain. Thus, as an article is introduced into the security system, its size, as indicated in signals provided from measurement by the inlet light curtain, is storable in the system data base for security purposes. The same may be said of the weight scale in the security zone, i.e., the systems of the commonly-assigned patents may look to weight or size as the measured article characteristic, or jointly to both such security parameters.
U.S. Pat. No. 5,340,970 (hereafter “the '970 patent”) discloses an override feature of the above described systems which enables an operator to correct the corresponding measurable characteristic information in the security database. Thus, if an item is improperly returned to the customer because the measurable characteristic of the product stored in the security database is incorrect, the information may be updated by supervisory personnel. Suitable additional measures (operator authorization code input) may be taken to insure that the override is indeed authorized. Once the override is effected, article rejection will only occur again if the measurable characteristic of the particular item is beyond the scope of the range of acceptable values which were updated by supervisory personnel.
The problem with manual updating is that it is grossly inefficient. The rejection of items necessitates store personnel correcting the data and having to visit individual self-checkout lanes as the rejections occur. This results in a delay for the customer, and higher costs by the retail establishment in stationing supervisory personnel and the potential of lost future sales from dissatisfied customers.
Accordingly, there exists a need to be able to automatically optimize the measurable characteristic information contained in the security database without direct human intervention each time a product is rejected during a transaction. This need stems also from the issue of insuring that the system provides reliable security to the store owner (returning items to the customer that should be returned) while also minimizing unnecessary delays to the customer.